Antibody inks could replace ELISA in biomedical research

Advanced printing technology is being used to produce stamp-sized testing patches that could replace the microwell plates used for routine biomedical testing.

A team from Swansea University envisages a situation where every hospital has a specially adapted printer and antibody inks to produce made-to-order reams of testing-patch cut-outs.

The technology is aiming to replace enzyme-linked immunosorbent assays (ELISA), which use 96-well microplates for all manner of biomedical research work and diagnostics.

While relatively simple in principle, they still require a skilled laboratory technician to operate, thus automated solutions have been muted for many years.

A team of engineers at Swansea, which specialises in flow dynamics, was approached to come up with an alternative technology.

Rather than trying to build one of the much-hyped ‘lab-on-a-chip’ devices — which often require supporting electronics, pumps or valves — the team looked for a simpler approach.

‘We were basically aiming to scale it down and make it easy to mass produce, plus cut down on labour, costs and expertise,’ researcher Chris Phillips of Swansea told The Engineer.

The project also gathers several partner organisations, including Micropharm, which produces antibodies at its base in Newcastle Emlyn; Abertawe Bro Morgannwg University NHS Trust; and Innovia Films of Kimbra, which will provide advice on the choice of substrate and materials.

‘The challenge was basically not killing the antibodies and getting them to stick to the surface,’ said Phillips.

‘We had to engineer a coating — something that’s compatible with existing printing processes, but bearing in mind that you can’t use solvents and you’ve got to get reasonable transfer with a difficult ink formulation. It’s essentially a compromise between print quality and antibody survival.’

The team’s solution was an antibody-based ink with a mixture of polymers selected for the right rheology — or flow characteristics — with salts to keep it stable.

Prof Tim Claypole of Swansea, who also worked on the project, said in a statement: ‘Volume printing is the most practical method to achieve low-cost disposable sensor technology. This will take innovation from the bench to the bedside and develop the tools and technologies to move the process of diagnosis forward and bring it into the surgery and home.’